package com.example.ourradio;

import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.support.v4.app.NavUtils;
import android.annotation.TargetApi;
import android.content.SharedPreferences;
import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
import android.os.Build;
import android.preference.PreferenceActivity;

public class SettingsActivity extends PreferenceActivity 
	implements OnSharedPreferenceChangeListener {

	@SuppressWarnings("deprecation")
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		
		// Loads the XML preferences file
        addPreferencesFromResource(R.xml.preferences);
	}

	@SuppressWarnings("deprecation")
	@Override
    protected void onResume() {
        super.onResume();

        // Registers a listener whenever a key changes            
        getPreferenceScreen()
         .getSharedPreferences()
         .registerOnSharedPreferenceChangeListener(this);
    }
  
	@SuppressWarnings("deprecation")
	@Override
    protected void onPause() {
        super.onPause();

       // Unregisters the listener set in onResume().
       // It's best practice to unregister listeners when your app isn't using them to cut down on 
       // unnecessary system overhead. You do this in onPause().            
       getPreferenceScreen()
        .getSharedPreferences()
        .unregisterOnSharedPreferenceChangeListener(this);    
    }
	
	/**
	 * Set up the {@link android.app.ActionBar}, if the API is available.
	 */
	@TargetApi(Build.VERSION_CODES.HONEYCOMB)
	private void setupActionBar() {
		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
			getActionBar().setDisplayHomeAsUpEnabled(true);
		}
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.settings, menu);
		return true;
	}

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		switch (item.getItemId()) {
		case android.R.id.home:
			// This ID represents the Home or Up button. In the case of this
			// activity, the Up button is shown. Use NavUtils to allow users
			// to navigate up one level in the application structure. For
			// more details, see the Navigation pattern on Android Design:
			//
			// http://developer.android.com/design/patterns/navigation.html#up-vs-back
			//
			NavUtils.navigateUpFromSameTask(this);
			return true;
		}
		return super.onOptionsItemSelected(item);
	}

	// When the user changes the preferences selection, 
    // onSharedPreferenceChanged() restarts the feed activity as a new
    // task. Sets the refreshDisplay flag to "true" to indicate that
    // the main activity should update its display.
    // The main activity queries the PreferenceManager to get the latest 
	// settings.
    @Override
    public void onSharedPreferenceChanged(
    	SharedPreferences sharedPreferences, 
    	String key
    ) {    
        // Sets refreshDisplay to true so that when the user returns to the main
        // activity, the display refreshes to reflect the new settings.
        FeedActivity.refreshDisplay = true;
    }

}
